Choosing a framework to implement your web app is a trade off like any other design decision. Let's focus in on specifics and talk about what the trade off is that you make when you choose a framework. Specifically, I'm talking about MVC frameworks in PHP.

She looks at both sides mentioning the good (code organization, encourages secure coding) and the bad (MVC is defined differently by different people, "More Than One Way to Do It", code bloat). In the end, her recommendation is to look at what you're trying to accomplish and decide first if a framework is for you and your app and, of it is, select the right one for the job.